Regenerative reversing furnace



jan. 24; 1928.

. Lfwl J. KENNEDY REGENERATVE REVERSING FURNACE Filed May 7, 192l 2 Sheets-Shee l ITW. l.

INVENTORV ent intention re lurnaces and has 'ter its on* eased ettciency et operation ot are W invention illus 'l uc einlgiodied in open hearth steel tast may he embodied in other types acrativc reversing furnaces. Such have tivo regenerators, one 'lor the in' andthe other for theiucon1- i r`the outgoing gases oit combustion i a high temperature and a cousiderahlz7 greater volume than the incoi'ning air. The regenerators have to he huilt with sufficient space to talre care et the large volume et i outgoing rl`he regenerative s pacc is 'therefore too large tor eilicient handling et vthe incoming air'. Vllhen the incoming air is passed through the entire regenerative space. as has heretofore been the practice. U the air tends to loiv through a restricted area et the regenerater and to leave little,I it any. circulation 'through other parts ot the rcgenerater., such the corners and sides. The `voluine et air is too small to Weep through the entire regenerator. its ay consequence the heat is extracted from only that portion ot the rcgenerator through which the incoming air taires its channel. lthere therefore. a large heat loss. lVhen the 'l lace is reversed and the hot gases u are passed out again tlirough the regenera r they lind portions et the regenerator e ill at a cornanarativelyr high heat. so that kn the gases nass 'through the regenera il tot they are not reduced as much in tern- `nerature as they should be, or would he, it the entire regenerative space was properly cooled hv the incon'iinaair.

.ln order to etticiently utilize the entire ree generative space and to increase the temperature of the 'incoming air and decrease the temperature et' the outgoing;- gases he vond what. has hcretotore heen obtained, ll pass the incoming air through ditterent portiene ol" 'the regenerater successively. l torni the regenerators at the two ends et the :turnace into sections or, where the regenerators are already huilt in sections, l utilize such sections. 'the outgoing gases a aredirected through all et the sections et the rc cnerator in parallel, thus providing sutticient space. to accommodate their flow. lllhe incoming air is .tirst directed through one section ot the regenerator to the furnace :ter a portion et the cycle et operation, and

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then directed through another section et the rcgenerator to the l'urnace. liv so doing thc area ot the regenerative snace through which 'the air llou's reduced and. i air velocityY increased to such a degree that the air floris through `l scours ont the entire regenerative space. The area is sullicientloi/7 reduced so that the ali does not tend to forni short circuiting chaniuls through a 'portion only7 ot the checker. rl"ho result is a `more complete absorption ot the heat from 'the checker and more economical operation oit the furnace. ls above stated, the cold in comingl air has a volume considerably less than that ot the hot outgoing gases. ilowever, as the current of incoming; air flows through but a single regenerator section at a time, its velocity is somewhere about that ot the current it outgoing7 gases tlorving through the regenerator sections in parallel; or in other words, the velocities et .tloiv through the regcnerators et the incoming air and outgoing gases are approximately equalized.

lu the drawings which illustrate the preferred embodiment of the invention.

Figure l is a plan view partly in section et an open hearth furnace and its regen-- erative system;

lligure 2 is a vertical section through one end et the furnace, and

Figure 3 is a horizontal section through one end oil' a furnace illustrating a modilication.

Referring to 'the illustrated embodiment et the invention, an open hearth furnace is indicated at 2. The furnace is provided. with two regenerators 3 and 4., one regrnera tor serving to heaty the incoming air and the other regenerator to absorb heat from the outgoing gases during halt of the regenerative cycle after which the regenerators are interchanged, as is Well known in the operan tion et such furnaces. Each et the regenerators is shown as having two sections 3 and 3b, and Il and sth, respectively. As is shown in Figure l, each section is connected with the furnace chamber 5 hy means ot its own port. is shown in the drawings, the sections 3a and 3b et the regenerator 3 are conu nected with the furnace through the ports G and 6b, respectively. Similarly, the sections la and lh are connected with the furnace through the ports 7 and 7b, respectively', at the other end et' the tui-nace chamber. The

ports are supplied with fuel through the usual burners, 8, such uei being usually gas, such as coke oven gas or natural gas. The sections of the regenerator 3 are connected with a stack 9 through the ipes 10a and 10".V Similarly, the sections of tie other regenerator are connected with the stack through the pines 11a and 11h. These pipes are provi( ed with the usual dempers marked 12, 12, 13n and 13". The air is talren into the regenerators through the usual intake musliroom valves marked 1li", 14", 152l and 15",-

3 of the regenerator 3 and is delivered to the furnace chamber through the single port 6a. The velocity of the air is sufficiently increased through the regenerative space so that the flow trikes place through the entire checker Work of the section 3, Also, since the air is discharged into the furnace through a port having half the area. of the two outlet ports, the velocity of the incoming air as discharged into the furnace is increasedA so that a desirable blow'pipe action is obtained.

Usuallyan open hearth furnace is 'reversed every twenty minutes. 'Under such conditions, incoming air will iovv through the regenerator section 3* and port 6 for ten minutes and will then he directed through the regenerator section 3b and port 6b for the next ten minutes. The gas burners 8 in each port will, of course,be turned on While the air is entering through such port and will be shut of when the air is shut off from the port. After the twenty minute half cycle is completed, the flow is reversed through the fui-nace. The outgoing gases then ow outwardly through both of the sections 3'l and 3b in parallel. The incoming air is then passed through the heated.. regienerator V4, utilizing the sections 4 and 4 and their res ective ports 7a and 7", successively.

n Figure 3 is illustrated a. modification in which the section 3a of the redenerator is connected to a middle port l5, While the section 3* is connected to two outside ports 1 6 and 17 through which the air and gases w in parallel from and to the regenerator section 3b. The operation of this modification is similar to that shown in Figure 1. The outgoing gases pass out through all three ports 15, 16 and 17, while the incoming air passes in through the port 15 during the one- :,cemci half of the half cycle, and through the ports 16 and 1T during the other half of said, half c cle.

yWhile the resent invention has been illustrated as emiodied in au open hearth steel furnace, the invention may he otherwise einhodied within the scope of the following claims.

i claim 1. rhe method et operating a reversing vfurnace and its regenerators, which consists iii passing the outgoing hot gascs'through substantially the entire regenerative space of one regenerator and passing the incoming air first through one portion and thereafter through another portion of the other regenerator, during each half regenerative cycle, and thereafter reversing the How through the furnace and repeating the operation with the regenerators interchanged, and so on, substantially as described.

2. The method of operating a reversing furnace provided with regeneratois having sections, which consists in passing the outgoing hot gases through the sections of one regenerator in parallel and in passing the incoming air first through one section of the other regenerator to the furnace and there after through another section of the regenerator. and thereafter reversing the rior: f through the furnace and repeating the operation with the revenerators interchanged, und so ou, substantially as described. 73: The method of operating a reversing furnace and its regeiierators which consists in maintaining a heat exchange between the outgoin hot gases and substantially all parts o one regenerator and causing a heat exchange between the incoming air and first one ortion and thereafter another portion of t e other regenerator, substantially as described.

4. The method of bperating a reversing furnace and its regenlerators which consists in approximately equalizingthe velocities of flow throu h the regenerators of the incoming air an outgoing gases, substantially as described.

5. The method of operating a reversing y furnace havinA two regenerators each conf sisting of a p urality of sections, which includes directing the outgoing hot gases throu h the sections of either regenerator in paral el and directing the incoming air iirst throu h one section of the other regenerator and t en through another section of said regenerator, substantially as described.

G. The method of operating a furnace provided with regenerators having sections, which consists in passing theoutgoing gases through the sections of a regenerator in parallel, and passing the incoming air through the sections of the regenerator one at a. time.

7. The method of operatin a furnace proq vided with regenerators, w 'eh consista in heating a regenerator by 'passt going gases through substantia the hot ontiy its erire regenerative space, and thereafter utilizing sind regenerator to pre-heat the incoming air by passing' the incomin air fora period through one portion of t e regenerator and bassin the incoming air for another period throng another' portion of the regenerator.

8,. rlfhe method ot' operatin a furnace provided with regenerative cham ers which vconsists in passing the outgoin gases through a piuraiity ot regenerativeciambcrs in paraiiei. to heat such chambers, and passing thc incoming air through a heated regenerative chamber tor a period and afterward through another heating regenerative chamber for another cried, v l F9. T e method, et operating a furnace provided ith a piurarity of regenerative chambers at 'each end ci the furnace connected to the nrnace through different ports, which censmts in passing the outgoing gases 'thrnngh phiraiity of the chambers `and their ports in paralisi to heat such chambers, and thereafter passing the incoming air through a heated regenerative chamber and its port for a eriod and afterward through another beate regenerative' chamber and its port for another period.

it). A re eneiative reversing furnace having a com ustioni chamber, a plurality of regenerative chambers for each end of the furnace, means for Bassing the incoming air through one 'regenerative chamber and afteri l5 ward ihrough another regenerative chamber in, the sameKA endet the furnace, and means for directing the gas in each case towards substantially the same portion of the combustion chamber.

11. A regenerative reversing furnace having a combustion chamber, a pluralit of regenerative chambers at each and o the furnace havin independent ports connecting them Wit the combustion `chamber, means for passing the incomin air through one regenerator and afterwar through an` other regenerator at the same end ofthe furnace, the several ports being arranged to direct the air toward substantially the same portion of the combustion chamber.

12. A regenerative reversing'frrnacf comprising a combustion chamber, a pluialit of regenerative chambers connected to eaci end of the furnace and connected thereto .by valveless passages, and means for controlling the passage of heated gases and 1ncoming air through the re enerativechambers comprising valves at e cold ends of the regenerative chambers.

13. A regenerative reversing furnace comprising a combustion chamber, a luralty of regenerative chambers connectedp to each end of the furnace, means acting to WithdraviT the hot gases from the furnace through the regenerative chambers in parallel and to di.- rect the incoming air through a part only of the regenerative chambers at the samel time, comprising valves at the cold ends of the regenerative chambers.

In testimony whereof, I have hereunto set my hand.

JULIAN KENNEDY. 

